1. Field of the Invention
The present invention relates to triamino- and fluoroalkyl-functional organosiloxanes. More particularly, the present invention relates to a composition which comprises at least one aminoalkyl- and fluoroalkyl-functional organosiloxane containing hydroxyl groups and/or alkoxy groups, water, and optionally an alcohol and/or an acid. The present organosiloxanes contain hydroxyl groups and/or alkoxy groups and are formulated in aqueous compositions. The present organosiloxanes are completely or partially hydrolyzed, which is to say that they contain hydroxyl and/or alkoxy groups in the context of the equilibrium being established. The present invention furthermore relates to the preparation of the triamino- and fluoroalkyl-functional organosiloxanes and their use.
2. Description of the Background
Fluoroalkylalkoxysilanes and their corresponding polycondensates are well known, as well as their use as hydrophobicizing and olephobicizing agents, as described in, for example DE 834 002, U.S. Pat. No. 3,012,066, British Patent 935 380, DE 31 00 555, EP 0 382 557, EP 0 493 747, EP 0 587 667 and DE 195 44 763.
Fluoroalkylalkoxysilanes are usually not used in concentrated form, since they are extremely expensive products. Furthermore, fluoroalkylalkoxysilanes are not soluble in water.
In order to prepare sufficiently stable solutions or formulations of fluoroalkyl functional silanes and corresponding cocondensates, organic solvents or emulsifiers have been employed as described in, for example DE 34 47 636, DE 36 13 384, WO 95/23830, WO 95/23804, WO 96/06895, WO 97/23432 and EP 0 846 716.
A disadvantage of solvent- and emulsifier-containing formulations and of organosiloxanes with a high content of alkoxy groups is the fact that such systems are undesirable on ecological and work safety grounds. Efforts have, therefore, increasingly been made to provide water-based systems with the lowest possible content of volatile organic compounds (abbreviation: xe2x80x9cVOCxe2x80x9d).
Nitrogen-containing and aminoalkyl- and fluoroalkyl-functional organosiloxanes which are substantially free of alkoxy groups are known as water-soluble constituents in otherwise emulsifier- and surfactant-free compositions for rendering surfaces water-, oil- and dirt-repellent as described in DE 15 18 551, EP 0 738 771 and EP 0 846 717).
A relatively high content of aminoalkyl groups must always be used in the water-based systems mentioned in order to ensure a good solubility in water. On the other hand, a high content of aminoalkyl groups is counterproductive, since these groups have hydrophilic properties and, therefore, counteract the efforts to provide a system which, as far as possible, exhibits hydrophobic properties. A need continues to exist for water-soluble aminoalkyl- and fluoroalkyl-functional organosiloxanes, but which retain hydrophobic properties.
Accordingly, one object of the present invention is to provide a water-soluble aminoalkyl- and fluoroalkyl-functional organosiloxane which has acceptable hydrophobic properties.
Another object of the present invention is to provide organosiloxanes which have the highest possible number of fluoroalkyl groups in relation to the number of aminoalkyl groups.
Briefly, these objects and other objects of the present invention as hereinafter will become more readily apparent can be attained by an organosiloxane which has at least one triamino group of formula I:
[NHx(CH2)aNHy(CH2)bNHz]xe2x80x94xe2x80x83xe2x80x83(I)
wherein the group is bonded to at least one silicon atom via at least one N-bonded alkylene group having 1 to 4 C atoms, a and b are identical or different and are an integer ranging from 1 to 6, x is 0 or 1 or 2, y is 0 or 1, z is 0 or 1 or 2, with the proviso that (x+y+z)xe2x89xa64, and at least one Sixe2x80x94C-bonded fluoroalkyl group of formula II:
F3C(CF2)r(CH2)sxe2x80x94xe2x80x83xe2x80x83(II)
wherein r is 0 or an integer ranging from 1 to 18 and s is 0 or 2.
It has now been found, surprisingly, that a low-viscosity, that is to say preferably a viscosity of  less than 100 mPas, composition, which, as a rule it is clear to slightly opalescent and which is also outstandingly stable to storage for several months on dilution with water and comprises at least one water-soluble, triamino- and fluoroalkyl-functional organosiloxane containing hydroxyl groups and/or alkoxy groups or a mixture of corresponding organosiloxanes, water, and optionally a content of alcohol and/or a content of acid, can be prepared by i) mixing at least one aminoalkylalkoxysilane of formula IIIa:
NH2(CH2)2NH(CH2)2NH(CH2)3Si(Rxe2x80x2)j(OR)(3xe2x88x92j)xe2x80x83xe2x80x83(IIIa)
wherein R and Rxe2x80x2 are identical or different and are a linear or branched alkyl group having 1 to 4 C atoms and j is 0 or 1, and/or of formula IIIb:
[NH2(CH2)2]2N(CH2)3Si(Rxe2x80x2)k(OR)(3k)xe2x80x83xe2x80x83(IIIb)
wherein R and Rxe2x80x2 are identical or different and are a linear or branched alkyl group having 1 to 4 C atoms and k is 0 or 1, and/or a xe2x80x9cbis-productxe2x80x9d or a mixture of xe2x80x9cbis-productsxe2x80x9d of formula IIIc:
[NHx(CH2)aNHy(CH2)bNHz].[(CH2)cSi(Rxe2x80x2)d(OR)(3xe2x88x92d)]exe2x80x83xe2x80x83(IIIc)
wherein R and Rxe2x80x2 are identical or different and are a linear or branched alkyl group having 1 to 4 C atoms, a is an integer from 1 to 6, b is 1, 2, 3, 4, 5 or 6, c is 1, 2, 3 or 4, d is 0 or 1 e is 1, 2, 3, 4 or 5, x is 0 or 1 or 2, y is 0 or 1, z is 0 or 1 or 2, and with the proviso that (x+y+z)xe2x89xa64, where e in the case where (x+y+z)=0 assumes the numerical value 5, for (x+y+z)=1e=4, for (x+y+z)=2e=3, for (x+y+z)=3e=2, and in the case where (x+y+z)=4e=1; and ii) at least one fluoroalkylalkoxysilane of formula IV:
F3C(CF2)r(CH2)sSi(Rxe2x80x3)t(OR)(3xe2x88x92t)xe2x80x83xe2x80x83(IV)
wherein r is 0 or an integer of 1 to 18, s is 0 or 2 and t is 0 or 1, and R and Rxe2x80x3 are identical or different and are a linear or branched alkyl group having 1 to 4 C atoms. Optionally, an alcohol, water and/or a water/alcohol mixture can be added to this material and also optionally, a catalyst. These materials are allowed to react or they are reacted. That is, these components may be pre-hydrolyzed or they may be hydrolyzed and are then subjected to cocondensation. The alcohol is completely or partly removed, that is to say suitably down to residual amounts of less than 5% by weight, and then optionally, adjusting the resulting product mixture to a pH of  less than 12 by addition of an inorganic or organic acid. The composition suitably has a pH of  less than 11.
The present composition moreover has the effect of further improved liquid-repellent properties of a correspondingly treated mineral surfacexe2x80x94using both hydrophilic and hydrophobic standard test liquids (tests according to the xe2x80x9cTeflon(copyright) specification test kitxe2x80x9d from DuPont). Reference is made to the Examples here.
In particular, at a molar ratio of starting substances which are either an N-[Nxe2x80x2-(2-aminoethyl)-2-aminoethyl]-3-aminopropyltrialkoxysilane or an aminoalkylalkoxysilane of formula IIb or formula IIIc, to a fluoroalkylalkoxysilane having formula IV of 1:xe2x89xa63.5 preferably 1:3 to 1:0.5, particularly preferably 1:3 to 1:1, especially preferably 1:3 to 1:2, a particularly high fluoroalkyl group content can be achieved in the water-soluble cocondensates of the present invention.
The composition of the invention can be diluted with water in all proportions if desired. In the case of completely hydrolyzed systems, as a rule no additional alcohol, as a result of hydrolysis, is formed here. In general, compositions of the invention and dilute systems are outstandingly stable upon storage for more than 6 months.
The invention thus relates to a composition which comprises at least one organosiloxane containing hydroxyl groups and/or alkoxy groups and water, wherein the organosiloxane carries at least one triamino group of formula I:
[NHx(CH2)aNHy(CH2)bNHz]xe2x80x94xe2x80x83xe2x80x83(I)
wherein the triamino group is bonded to at least one silicon atom via at least one N-bonded alkylene group having 1 to 4 C atoms, a and b are identical or different and are each an integer of 1 to 6, x is 0 or 1 or 2, y is 0 or 1, z is 0 or 1 or 2, and with the proviso that (x+y+z)xe2x89xa64, and at least one Sixe2x80x94C-bonded fluoroalkyl group of formula II:
F3C(CF2)r(CH2)sxe2x80x94xe2x80x83xe2x80x83(II)
wherein r is 0 or an integer of 1 to 18 and s is 0 or 2.
The invention also relates to organosiloxanes which contain at least one triamino group of formula I:
[NHx(CH2)aNHy(CH2)bNHz]xe2x80x94xe2x80x83xe2x80x83(I)
wherein the triamino group is bonded to at least one silicon atom via at least one N-bonded alkylene group having 1 to 4 C atoms, a and b are identical or different and are each an integer of 1 to 6, x is 0 or 1 or 2, y is 0 or 1, z is 0 or 1 or 2, and with the proviso that (x+y+z)xe2x89xa64, and at least one Sixe2x80x94C-bonded fluoroalkyl group of formula II:
F3C(CF2)r(CH2)sxe2x80x94xe2x80x83xe2x80x83(II)
wherein r is 0 or an integer of 1 to 18 and s is 0 or 2.
Organosiloxanes of the invention are in general based on so-called [M], [D] and [T] structural units, which, as such, are familiar to the expert, it also being possible for the oligomeric and polymeric organosiloxane units to form aggregates. Such organosiloxanes usually carry hydroxyl groups and/or alkoxy groups as functional groups, in addition to the functional groups of the invention. The presence of hydroxyl and alkoxy groups can, as a rule, be controlled by the amount of water added during the preparation and the completeness of the removal of alcohol. Furthermore, the organosiloxanes of the invention can also contain, that is to say carry, alkyl groups having 1 to 16 C atoms as additional functional groups.
In particular, the organosiloxanes of the invention can be diluted with water in an outstanding manner. Low-viscosity, slightly opalescent liquids are in general obtained in this case. However, the organosiloxanes of the invention can also be dissolved in alcohol or incorporated into water-soluble emulsions.
Another aspect of the invention is a process for the preparation of an organosiloxane-containing composition, which comprises mixing i) at least one aminoalkylalkoxysilane of formula IIIa:
NH2(CH2)2NH(CH2)2NH(CH2)3Si(Rxe2x80x2)j(OR)(3xe2x88x92j)xe2x80x83xe2x80x83(IIIa)
wherein R and Rxe2x80x2 are identical or different and are each a linear or branched alkyl group having 1 to 4 C atoms and j is 0 or 1, and/or of formula IIIb:
[NH2(CH2)2]2N(CH2)3Si(Rxe2x80x2)k(OR)(3xe2x88x92k)xe2x80x83xe2x80x83(IIIb)
wherein R and Rxe2x80x2 are identical or different and are a linear or branched alkyl group having 1 to 4 C atoms and k is 0 or 1, and/or a xe2x80x9cbis-productxe2x80x9d or a mixture of xe2x80x9cbis-productsxe2x80x9d of formula IIIc:
[NHxCH2)aNHy(CH2)bNHz].[(CH2)cSi(Rxe2x80x2)d(OR)(3xe2x88x92d)]exe2x80x83xe2x80x83(IIIc)
wherein R and Rxe2x80x2 are identical or different and are a linear or branched alkyl group having 1 to 4 C atoms, a is an integer ranging from 1 to 6, b is 1, 2, 3, 4, 5 or 6, c is 1, 2, 3 or 4, d is 0, e is 1, 2, 3, 4 or 5, x is 0 or 1 or 2, y is 0 or 1, z is 0 or 1 or 2, and with the proviso that (x+y+z)xe2x89xa64, where e in the case where (x+y+z)=0 assumes the numerical value 5, for (x+y+z)=1 e=4, for (x+y+z)=2e=3, for (x+y+z)=3e=2, and in the case where (x+y+z)=4 e=1, and ii) at least one fluoroalkylalkoxysilane of formula IV:
F3C(CF2)r(CH2)sSi(Rxe2x80x3)t(OR)(3xe2x88x92t)xe2x80x83xe2x80x83(IV)
wherein r is 0 or an integer ranging from 1 to 18, s is 0 or 2 and t is 0 or 1, and R and Rxe2x80x3 are identical or different and are each a linear or branched alkyl group having 1 to 4 C atoms, adding water or a water/alcohol mixture and, if appropriate a catalyst to the combined materials, allowing the components to react and completely or partly removing the alcohol. The product mixture thus obtained is brought to a pH of  less than 12, preferably to 4 to 7 by addition of an inorganic or organic acid.
Still another aspect of the invention is a composition which is prepared by the process of the invention. The invention is also directed to triamino and fluoroalkyl-functional organosiloxanes the invention, in particular mixtures thereof, which are prepared by the process of the invention.
N-[Nxe2x80x2-(2-Aminoethyl)-2-aminoethyl]-3-aminopropyltrimethoxysilane (DYNASYLAN(copyright) TRIAMO) is preferably employed as a compound of formula IIIa in the present process.
An example which may be mentioned of a compound having formula IIIb is
(H2Nxe2x80x94CH2CH2)2Nxe2x80x94(CH2)3Si(OCH3)3,
xe2x80x9cBis-productxe2x80x9d in the context of the present invention is understood to mean those compounds having formula IIIc, such as, for example, the formula
(H3CO)3Si(CH2)3NH(CH2)2NH(CH2)2NH(CH2)3Si(OCH3)3.
However, a mixture of triaminoalkyl-functional alkoxysilanes can also be employed in the process of the invention.
Tridecafluoro-1,1,2,2-tetrahydrooctyltrimethoxysilane or tridecafluoro-1,1,2,2-tetrahydrooctyltriethoxy-silane (DYNASYLAN(copyright) F8261) is preferably employed as the fluoroalkylalkoxysilane of formula IV in the present process. However, mixtures of several fluoroalkylalkoxysilanes can also be employed.
The alkoxysilanes which are employed in the present process preferably include methoxy- and ethoxysilanes. If an alcohol is added during the process, methanol or ethanol can accordingly be used.
A protonic acid or a mixture of protonic acids is particularly suitable as the catalyst. Thus, for example, formic acid, acetic acid and hydrogen chloride can be employed in the process of the invention. These acids can furthermore also be used to adjust the pH of the composition of the invention.
In the process according to the invention, i) at least one triaminosilane of formulae IIIa to IIIc and ii) at least one fluoroalkylsilane of formula IV are employed in a molar ratio of i/iixe2x89xa70.29, preferably 0.3 to 2, particularly preferably 0.33 to 0.5.
The concentration of the organosiloxanes in the aqueous solution of the invention is furthermore suitably adjusted to an active compound content of  less than 50% by weight. An active compound content above 50% by weight can lead to gel formation or severe clouding.
In particular, the content of organosiloxane in the composition of the invention is 0.005 to 40% by weight, preferably 0.01 to 20% by weight, particularly preferably 0.05 to 15% by weight, especially preferably 0.1 to 5% by weight.
The process of the invention is in general conducted so that aminoalkylalkoxysilanes of formulae IIIa to IIIc and fluoroalkylalkoxysilanes of formula IV are mixed. An alcohol is added if desired, and the components are hydrolyzed together and subjected to cocondensation. The alcohol, including the hydrolysis alcohol, is then removed by distillation. Mixing of the alkoxysilanes can take place over a temperature range from the solidification point to the boiling point of the silanes employed. As a rule, water is added in excess to the silane mixture in order to conduct hydrolysis. Hydroxyl-functional organosiloxanes are as a rule obtained by this procedure. However, the hydrolysis or cocondensation can also be conducted with a stoichiometric amount or a stoichiometrically deficient amount of water. If the amount of water added during the reaction is limited to less than 3 mol of water per mol of Si compound employed, substantially alkoxy-containing organosiloxanes of the invention can be prepared. The organosiloxanes of the invention are usually obtained as a mixture in the reaction.
The reaction of the invention is, in general, conducted at a temperature in the range of 0 to 100xc2x0 C. The reaction of the invention is suitably conducted at a pH of 4 to 12. The hydrolysis preferably takes place at a temperature of  less than 100xc2x0 C., particularly preferably at  less than 90xc2x0 C., and especially preferably at  less than 60xc2x0 C. A good thorough mixing, for example by stirring, is as a rule ensured. The reaction described can furthermore be conducted in the presence of a catalyst.
As a rule, in the process of the invention the alcohol or hydrolysis alcohol is removed by distillation, the distillation preferably being conducted at a temperature of  less than 90xc2x0 C., particularly preferably at  less than 60xc2x0 C., and suitably under reduced pressure, since this protects the product. The content of alcohol in the composition is suitably lowered here to less than 5% by weight, preferably to less than 1% by weight, particularly preferably to less than 0.5% by weight.
The distillation can advantageously be conducted in a distillation column and can be continued until no further alcohol can be detected at the top of the column, where the desired product is obtained at the bottom and can be further worked-up, if appropriate. If suspended matter is formed, it can be removed from the product by means of filtration, sedimentation, centrifugation or similar such standard processes.
The composition of the invention can be applied from a 50% strength solution or a dilute solution. Water, for example, can be used as the diluent. In principle, however, the composition of the invention can also be diluted with a corresponding alcohol.
The present invention also relates to compositions which comprise the organosiloxanes of the invention, for example, but not exclusively, those which are employed for hydrophobicizing and/or oleophobicizing surfaces, for xe2x80x9canti-graffitixe2x80x9d applications, for xe2x80x9ceasy-to-cleanxe2x80x9d applications, to name only a few.
Compositions of the invention can thus be used in an outstanding manner as compositions for hydrophobicizing and/or oleophobicizing surfaces, as building protection compositions, as compositions for treatment of concrete, naturally occurring mineral substances and glazed and non-glazed ceramic products, as an additive in formulations for surface treatment, for xe2x80x9canti-graffitixe2x80x9d applications and in compositions for xe2x80x9canti-graffitixe2x80x9d applications, for xe2x80x9ceasy-to-cleanxe2x80x9d applications and in compositions for xe2x80x9ceasy-to-cleanxe2x80x9d applications, as water-soluble adhesion promoters, as a constituent in coating systems and in anticorrosion compositions, for biocidal treatment of surfaces, for treatment of wood, for treatment of leather, leather products and furs, for treatment of glass surfaces, for treatment of plateglass, for treatment of surfaces of plastics, for the preparation of pharmaceutical and cosmetic products, for modification of glass and mineral surfaces and glass and mineral fiber surfaces, for production of artificial stones, for wastewater treatment, for surface modification and treatment of pigments and as a constituent in paints and coatings.